Apparatus for closing containers



July 25, 1967 G. B. COOPER 2 APPARATUS FOR CLOSING CONTAINERS Filed July 6. 1964 4 Sheets-Sheet 1 Inventor GRAHAM B. CQOPER rney July 25, 1967 G. B. COOPER 2 APPARATUS FOR CLOSINGCONTAINERS Filed July 6. 1964 4' Sheets-Sheet 2 Inventor GRAHAM B CO0PE'R grwau 1 A ttorney;

APPARATUS FOR CLOSING CONTAINERS Filed July 6. 1964 4 Sheets-Sheet 3 la 22- g 25' Z 26% l 7 I 24- -Invefilor GRAHAM a. COOPER ttorneyg July 25, 1967 G. a. COOPER 3,332,201

APPARATUS FOR CLOSI NG CONTAINERS Filed July 6. 1964 4 Sheets-Sheet 4 v Inventor VGRAHAM a. COOPER v A ttqrn e United States Patent 3,332,201 APPARATUS FOR CLOSING CONTAINERS Graham Baptie Cooper, London, England, assignor to The Metal Box Company Limited, London, England, a British company Filed July 6, 1964, Ser. No. 380,356 Claims priority, application Great Britain, July 24, 1963, 29,385/ 63 5 Claims. (CI. 53-88) This invention relates to apparatus for changing the gaseous content of containers prior to closing the con tainers, particularly non-permeable containers such as plastic or metal containers or glass bottles, and relates in particular to apparatus for removing air from a container one end of which is open and the contents of which are already disposed therein and for replacing the air with a gas, for example nitrogen, inert to the contents of the container, with hydrogen, or with a gaseous mixture consisting of hydrogen and a gas inert to the contents of the container.

As is well understood, some products, such for example as dried milk or other edible or non-edible products, deteriorate in the presence of oxygen and cannot always be packed in the normal manner in an airtight container because residual air in the headspace of the container will affect the product and when packing such products it is usual to employ a technique known as gas packing which may, for example, consist of placing a batch of filled containers, in a gas-tight cabinet, exhausting air by means of a pump, and then admitting an inert gas, usually nitrogen, into the cabinet until atmospheric pressure is restored. When using this technique it is necessary to provide a hole in each container and this hole must be sealed, normally by soldering, at the end of the gassing operation. Examples of foodstuffs packed by this process are dried milk, dehydrated foods, and nuts.

Gas packing in this manner is a laborious and expensive process compared with packing processes which can be effected in continuous manner by feeding containers one at a time in succession to a sealing machine. Further, in some instances, as when packing full cream spray-dried milk which has a notorious ability to occlude air, a single gassing cycle as described above is not sufiicient to remove all oxygen. The powder must either be given a bulk degassing treatment before packing or alternatively the filled containers must be given two gassing cycles spaced by an interval of several days'to allow occluded air to diffuse into the headspaces of the containers.

It has been proposed to dispose of the residual amount of oxygen in a hermetically sealed filled container by introducing hydrogen or hydrogenmixed with an inert gas into the container and in the presence of a catalyst, such as finely divided palladium metal, to combine the hydrogen With the residual oxygen in the container. In this proposal the catalyst may be introduced in the form of palladium powder deposited on granules of ceramic or alumina and enclosed in a perforated sachet attached to the inner side of one end of the container.

It is a main object of the present invention to provide apparatus which Will permit the changing of the gaseous content of containers and the hermetic sealing thereof as a continuous process in which the containers, with the contents disposed therein, can be fed one at a time in succession to a sealing machine.

According to the invention there is provided apparatus for changing the gaseous content of a container one end of which is open and the contents of which are already disposed therein, said apparatus comprising a rotatable conveyor operable to receive containers and to move them in succession and in spaced relation in one direction with the open ends thereof uppermost, a pillar co-axial with and rotatable with the conveyor, arms extending laterally from the pillar and each having a vacuum port and gas port formed therein, a hollow spindle supported by each arm for axial movement relative to the arm selectively to connect the interior of the spindle with said vacuum port and gas port, a cam co-operating with said spindle and movable thereby to effect said axial movements thereof, a pad carried by each spindle and movable thereby to effect a gas-tight seal with the top of a container during extraction of air from the container through the pad and spindle and the introduction of gas into the container through the pad and spindle, vacuum-creating means, and gas-introducing means and operable to control the Withdrawal of air from the container and the introduction of gas into the container, and means cooperating with each pad to impede the withdrawal of the contents from the container during the withdrawal of air therefrom.

The pillar may be hollow and the interior divided into a vacuum chamber and a gas chamber separate one from the other, the vacuum chamber being connected with the vacuum-creating means and the vacuum port and the gas chamber connected with the gas-introducing means and the gas port.

The valve means for each pad may comprise a stationary sleeve carried by the arm supporting the pad, the pad spindle being slidable axially in the sleeve and the sleeve provided with annular recesses spaced apart, axially thereof and sealed from each other and from atmosphere by O-rings making sliding sealing engagement with the pad spindle, one of said recesses being in communication with the vacuum chamber and the other with the gas chamber and the pad spindle being provided with a laterally extending port communicating with the hollow interior of the spindle and movable by the spindle into positions at which the laterally extending port is aligned with one or the other of the recesses or is obtrurated therefrom.

A single stationary cam may effect all axial movements of each pad spindle against the action of a return spring.

The means for impeding the withdrawal of the contents from a container may comprise a filter capable of preventing the passage therethrough of fine powdery material such as dried milk.

In order that the invention may be clearly understood one embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which:

FIGURE 1 is a diagrammatic elevation of a sealing machine embodying apparatus according to the invention,

FIGURE 2 is a top plan of FIGURE 1,

FIGURE 3 is a diagrammatic plan showing conveyor means by which containers are introduced and moved in succession through the machine,

FIGURE 4 is an elevation, partly in section, of apparatus according to the invention,

FIGURE 5 is a section of a part of the apparatus shown in FIGURE 4,

FIGURE 6 is a section of another part of the apparatus shown in FIGURE 4, and

FIGURE 7 is a plan of FIGURE 6.

Referring to the drawings the machine diagrammatically illustrated in FIGURES 1 to 3 is a machine for sealing cans and the portion 1 of the machine is a known kind of machine referred to in the art as a seamer fitted with undercover gassing equipment. This machine, being known per se, will not be described in detail but it is arranged to receive open-topped filled cans one at a time, to feed can ends 2, FIGURE 1, from a magazine 3 on to the tops of the cans and then to seam the can ends on to the cans. Just before a can end is seamed on to the can and while the can end is slightly spaced from the top of the can gas,

which may be a gas, such as nitrogen, inert to the contents of the can, hydrogen, or a mixture of hydrogen and a gas inert to the contents of the can, is delivered from a source 4, under control of a valve mechanism 5, FIGURE 2, beneath the can end and into the headspace of the can. The machine is known as a seamer fitted with undercover gassing equipment because the gas is delivered into the can under the cover afforded by the can end which is so supported as to direct the gas into the headspace.

A conveyor, shown in the drawings as a continuously rotatable spider 6, FIGURE 4, receives cans 7 one at a time from a transfer conveyor 8, FIGURE 2, and moves them in succession and in spaced relation in one direction with the open ends of the cans uppermost. The transfer conveyor 8 receives the cans as they are moved away from a filling machine, not shown.

As each can 7, FIGURE 4, is received by the rotatable spider 6 it rests on a support 9 and is located beneath a pad 10 supported for movement into and out of engagement with the open end of the can to effect a gas-tight seal therewith. The pad 10 is made of compressible material, preferably rubber, and has a diameter such that it can be employed to effect the sealing of a range of cans of differing diameters.

Each pad 10 is mounted on a hollow spindle 11, FIG- URE 4, which is carried by an arm 12 extending laterally from a pillar 13 which is co-axial with and rotatable with the spider 6. The upper end of each spindle carries a cam follower roller 14 arranged to co-operate with a stationary cam 15 which effects axial movements of the pad against the action of a return spring 16. Stops 17 limit the extent of upward movement of the pads by the springs 16. The cam 15 is so contoured as to first cause a pad to be firmly pressed against the open top of a can and to be connected with a vacuum-creating means 18, FIGURE 1, for example a vacuum pump, and then to be raised slightly and connected with a gas-introducing means 19, for example a gas container, by which gas, such as nitrogen, hydrogen, or a mixture consisting of hydrogen and nitrogen, is introduced into the can to restore the pressure in the can to atmospheric pressure.

The connection of the pads with the vacuum-creating means and the gas-introducing means is controlled by valve means which in the embodiment of the invention shown in the drawings is integral with the arms 12. The pillar 13 is hollow and the interior is divided by a member 20, FIGURE 4, to form a vacuum chamber 21 and a gas chamber 22 which are separate one from the other. The vacuum chamber 21 is connected by a flexible tube 23 with the vacuum-creating means 18 and the gas chamber 22 is connected by a tube 24 with the gas-introducing means 19. The vacuum chamber 21 is also connected with a vacuum port 25 formed in each arm 12. The gas chamber is also connected with a tube 26 and a gas port 17 formed in the arm 12.

Each hollow spindle 11 is slidable axially in a stationary valve sleeve 28, FIGURES 4 to 6, provided with annular recesses 29, 30 spaced apart axially of the sleeve. The re- 7 cesses 29, 30 are sealed from each other and from atmosphere by O-rings 31 which make sliding engagement with the spindle 11. The recess 29 is in communication with the vacuum chamber 21 through the vacuum port 25 and the recess 30 is in communication with the gas chamber a 22 through the gas port 27. The spindle 11 is provided with a laterally extending port 32 which communicates with the hollow interior 33 of the spindle and axial movement of the spindle by the return spring 16 causes the laterally extending port 32 to be obturated while movement of the spindle under control of the cam 15 causes the laterally extending port 32 to be aligned either with the recess 29 or with the recess 30.

Each pad 10 has co-operating therewith an element 34 arranged to impede the withdrawal of the contents from the container when the vacuum is applied thereto to withdraw air therefrom and when the contents are powdery materials such as dried milk the element 34 is a filter capable of preventing the passage of the powdery material therethrough.

When the apparatus is in operation the spider 6 is rotated continuously and as a can is engaged thereby the spindle 11 is moved downwards by the cam 15 so that the pad 10 makes sealing engagement with the top of the can and the laterally extending port 32 is aligned with the recess 29 thus causing air to be drawn out of the container. Continued rotation of the spider causes the follower roller 14 to be engaged with that part of the contour of cam 15 which permits the spindle 11 to rise until the laterally extending port 32 is aligned with the recess 30 thus permitting gas to be introduced into the container. This is continued until the gas restores atmospheric pressure in the can following which the can is moved by the spider 6 to an endless intermittent conveyor 35, FIGURE 3, by which the can is moved into the sealing portion 1 of the machine. The introduction of gas, which may be nitrogen, hydrogen, or a mixture of hydrogen and nitrogen, into the can in the sealing portion 1 of the machine is effective to remove air which may have entered the can during the very short interval of time between the can leaving the spider 6 and being introduced into the sealing portion of the machine by the conveyor 35. Thus it will be under stood that by the use of apparatus according to the invention the invention the quantity of residual air in a container is reduced to a minimum and the process of removing air and of introducing the gas which replaces the extracted air, and sealing of the container is a continuous process economically effected by a relatively simple form of apparatus.

When a catalyst is to be included in the container the introduction thereof into the container may be effected in any desired manner for example the catalyst may be applied to a carrier therefor which is inserted into the container before the contents, or which is inserted into the container as it passes into the sealing portion of the machine, or it may be pre-applied to the inner surfaces of the can ends 2.

If desired, the vacuum chamber 21 may be connected to the arms 12 by tubes similar to the tubes 26.

As described with reference to the drawings the sealing station of the machine has been referred to as adapted for seaming can ends to open-topped cans but it is to be understood that instead of this form of sealing there may be used other sealing methods capable of affixing gas-tight covers to cans or jars.

I claim:

1. Apparatus for changing the gaseous content of a container one end of which is open and the contents of which are already disposed therein, said apparatus comprising a rotatable conveyor operable to receive containers and to move them in succession and in spaced relation w th the open ends thereof uppermost, a pillar co-axial with and rotatable with the conveyor, arms extending laterally from the pillar and each having a vacuum port and a gas port formed therein, a hollow spindle supported by each arm for axial movement relative to the arm selectively to connect the interior of the spindle with sa d vacuum port and gas port, a cam co-operating with said spindle to effect said axial movements thereof, a pad carried by each said spindle and movable thereby to effect a gas-tight seal with the open top of a container during extraction of air from the container through the pad and spindleand the introduction of gas into the container through the pad and spindle, vacuum-creating means and gas-mtroducing means connected respectively with said vacuum and gas ports, valve means co-operating with said pad, vacuum-creating means, and gas-introducing means and operable to control the withdrawal of air from the container and the introduction of gas into the container, and means co-operating with each pad to impede the withdrawal of the contents from the container during the withdrawal of air therefrom.

2. Apparatus for changing the gaseous content of a container one end of which is open and the contents of which are already disposed therein, said apparatus comprising a rotatable conveyor operable to receive containers and to move them in succession and in spaced relation with the open ends thereof uppermost, a hollow pillar the interior of which is divided into a vacuum chamber and a gas chamber separate one from the other, said pillar being co-axial with and rotatable with the conveyor, arms extending laterally from the pillar and each having a vacuum port and a gas port communicating respectively with said vacuum and gas chambers, a hollow spindle supported 'by each arm for axial movement relative to the arm selectively to connect the interior of the spindle with said vacuum port and gas port, a cam co-operating with said spindle to eifect said axial movements thereof, a pad carried by each said spindle and movable thereby to effect a gas-tight seal with the open top of a container during extraction of air from the container through the pad and spindle and the introduction of gas into the container through the pad and spindle, vacuum-creating means and gas-introducing means connected respectively with said vacuum and gas chambers, valve means co-operating with said pad, vacuum-creating means, and gas-introducing means and operable to control the withdrawal of air from the container and the introduction of gas into the container, and means co-operating with each pad to impede the withdrawal of the contents of the container during the withdrawal of air therefrom.

3. Apparatus according to claim 2, wherein the valve means for each pad comprises a stationary sleeve carried by the arm supporting the pad and in which the pad spindle is axially slidable, said sleeve being provided with annular recesses spaced apart axially thereof and sealed from each other and from the atmosphere by O-rings making sliding sealing engagement with the pad spindle, one of said recesses being in communication with said vacuum chamber and the other with said gas chamber, and the pad spindle being provided with a laterally extending port communicating with the hollow interior of the spindle and movable by the spindle into positions at which the laterally extending port is aligned with one or other of said recesses or is obturated therefrom.

4. Apparatus according to claim 3, wherein the means for impeding the Withdrawal of the contents from a container comprises a filter capable of preventing the passage therethrough of fine powdery material such as dried milk.

5. Apparatus according to claim 2, wherein the means for impeding the withdrawal of the contents from a container comprises a filter capable of preventing the passage therethrough of fine powdery material such as dried milk.

References Cited UNITED STATES PATENTS 2,496,877 2/ 1950 Krueger 53-22 X 2,610,779 9/1952 Fouse 53-88 X 3,220,153 11/1965 Cormack et a1 5322 TRAVIS S. MCGEHEE, Primary Examiner. 

1. APPARATUS FOR CHANGING THE GASEOUS CONTENT OF A CONTAINER ONE END OF WHICH IS OPEN AND THE CONTENTS OF WHICH ARE ALREADY DISPOSED THEREIN, SAID APPARATUS COMPRISING A ROTATABLE CONVEYOR OPERABLE TO RECEIVE CONTAINERS AND TO MOVE THEM IN SUCCESSION AND IN SPACED RELATION WITH THE OPEN ENDS THEREOF UPPERMOST, A PILLAR CO-AXIAL WITH AND ROTATABLE WITH THE CONVEYOR, ARMS EXTENDING LATERALLY FROM THE PILLAR AND EACH HAVING A VACUUM PORT AND A GAS PORT FORMED THEREIN, A HOLLOW SPINDLE SUPPORTED BY EACH ARM FOR AXIAL MOVEMENT RELATIVE TO THE ARM SECLECTIVELY TO CONNECT THE INTERIOR OF THE SPINDLE WITH SAID VACUUM PORT AND GAS PORT, A CAM CO-OPERATING WITH SAID SPINDLE TO EFFECT SAID AXIAL MOVEMENTS THEREOF, A PAD CARRIED BY EACH SAID SPINDLE AND MOVABLE THEREBY TO EFFECT A GAS-TIGHT SEAL WITH THE OPEN TOP OF A CONTAINER DURING EXTRACTION OF AIR FROM THE CONTAINER THROUGH THE PAD AND 